This invention relates to electrical apparatus, such as electrical meters or power monitoring devices, and comprises a unique and advantageous construction therefor. Electrical apparatus such as meters or monitors frequently contain batteries for their temporary or emergency operation during power outages, and which require periodic replacement. Additionally, some of the more sophisticated apparatus of this type currently available include integral electrical programming and/or testing systems whereby predetermined plans or schemes of performance conditions, and/or evaluating test procedures, can be programmed into the apparatus by means of externally applied electrically transmitted instructions and activation. For instance, an independent programming or testing instrument is temporarily connected with the apparatus through electrical contacts, and a programmed scheme is established in the apparatus, and/or its operation is evaluated, through electrical currents or impulses transmitted therebetween.